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    <title>Document</title>
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    <script>
        var a=10;
        var b=5;

       var c= a++ + ++a + b-- + --a + --b + a++;
         /* 
         var c=10 + 12  + 5  +  11  +  3  +  11
         
         内存   11   12   4    11     3      12
         */
  
         console.log('a='+a,'b='+b,'c='+c);// 12    3   52      a=12 b=3 c=52

         var a1=a++;
         var a2=++a;
         var b1=b--;
         var a3=--a;
         var b2=--b;
         var a4=a++;
         var c=a1+a2+b1+a3+b2+a4;
    </script>
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